(a) Field of the Invention
This invention relates to a microscope whereby a sample can be observed over a wide range.
(b) Description of the Prior Art
Generally a microscope is formed fundamentally of an objective, an eyepiece and a stage for holding a sample observing position, the sample held on the stage or the stage itself used to be moved in the direction vertical to the optical axis. However, with the recent development of the peripheral technique, such large samples as brain slices and large silicon wafers have increased. Therefore, in the case of observing such large sample, the stage mounting the sample must be moved in a wide range, that is, over the range B which is 4 times as large as the range A to be observed in FIG. 1, therefore the strength of the entire microscope including the stage is required and the stage moving mechanism must be large. For example, if the size of the sample to be observed becomes twice as large, the stage moving range will become 4 times as large, therefore, the entire microscope will be larger, the inertia of the stage itself will be larger and therefore the position precision will be more difficult to control.
On the other hand, according to Japanese preliminary patent publication Sho No. 59-86020, there is suggested a method wherein a first objective and second objective are provided and only the first objective is moved in the direction perpendicular to the optical axis to change the sample observing position. However, there are defects that, in order to change the observing position of a large sample by this method, a very large objective will be required, the observable range will be varied by the magnification of the objective and further so large observing range will not be obtained due to the field number of the eyepiece.